In a catalytic converter for cleaning exhaust gas of an automobile, a monolithic type carrier is generally accommodated in a metallic shell while covered on the outer circumference thereof with a mat having various functions of retention, cushioning or sealing. The mat is made of a flexible flat sheet mainly composed of ceramic fibers and wound around substantially entirely the cylindrical outer circumference of the carrier. Usually, the mat is secured to the carrier not to move within the interior of the metallic shell. A double-coated pressure sensitive adhesive tape capable of being easily handled is used as such securing means.
The catalytic converter of the above-mentioned structure is conventionally assembled in the following manner. First, the mat cut to have a desired shape is disposed in a flatly extended state, and the double-coated pressure sensitive adhesive tape having a release paper clad on one surface thereof is located and adhered to a proper position of one surface of the mat. Then, the release paper is peeled off from the adhered double-coated pressure sensitive adhesive tape. Subsequently, the mat is wound around the outer circumference of the carrier while the surface of the mat carrying the double-coated pressure sensitive adhesive tape is in tight contact with the outer circumference of the carrier, whereby the mat is fixed thereto by the double-coated pressure sensitive adhesive tape. And, the carrier is accommodated in the metallic shell together with the mat secured to the outer circumference thereof.